1. Field of the Invention
The present invention relates to a beam spot position control device and beam spot position control method, and an optical disk recording and reproducing device for irradiating multiple beam spots onto a disk-shaped recording medium and for recording and reproducing information.
2. Description of the Related Art
An optical disk recording and reproducing device normally irradiates a single spot of light which has been collected by an objective lens onto an information track formed beforehand on an optical disk, and performs signal recording and signal reproducing. The information track normally is formed in a spiral shape from the innermost portion of the optical disk towards the outer side, or from the outermost portion towards the inner side, and therefore by the optical disk recording and reproducing device performing tracking control to the track, the signals are written or read sequentially.